Technical Field
The embodiments described and claimed herein relate generally to securing a mobility device (e.g. wheelchair, scooter, stretcher, etc.) using a “tensioner” that induces tension into a restraint to provide greater stabilization while the mobility device is being transported in a vehicle (although it could be used to transport it outside of a vehicle). In one embodiment, the tensioning device induces tension into a designated front restraint (which is attached to a point on a mobility device), and urges the mobility device toward or into contact with a “bumper”. The combination of the tensioner and bumper acts to further stabilize the mobility device while being transported. While it could be used in a 4-point mobility device restraint configuration, it is envisioned and most beneficial when used in a 2 or 3-point restraint system configuration, such as those disclosed in U.S. Pat. No. 9,107,786 and U.S. Patent Publication No. 2014-0334893.
Background Art
Historically, mobility device securement systems had been designed with four restraints, one attached to each corner of the mobility device (two in front, two in rear). Recently, new systems have been developed with less than four attachment points (e.g., Q'Straint's Q'Pod and American Seating's Reliant). These systems have used three attachment points instead of four, and they include a tensioning device to help stabilize the mobility device while being transported.
One challenge is vehicle (e.g. bus) wall seating systems are becoming thinner in order to allow for larger aisle clearances; this is important to allow mobility device passengers to maneuver, and others passengers to pass in aisle when mobility device passengers are occupying the securement areas. Often times, two mobility device securement systems (i.e. Q'Pods) are installed side-by-side, and when occupied simultaneously by two mobility device passengers, the clear aisle spacing is limited or non-existent, which causes issues. Also, many vehicle retrofit opportunities pose difficult challenges as there are often times existing fixed obstructions such as heating & cooling ducts and wheel-wells that are impossible or very costly to remove. In these instances, current systems with tensioners are unable to be installed in these applications and the only current alternative is the traditional 4-point system which is less effective, especially in a city bus environment where limiting dwell times are critical.
Various embodiments of the Q'Pod's tensioning devices are disclosed in U.S. Pat. No. 9,107,786 at, for example, FIGS. 5 and 11-15. In the Q'Pod's current design, twisting of handle is required to release the mechanism, which could be awkward for some users. In addition, the twisting action increases the “knuckle clearance” required by certain standards. Knuckle clearance on all sides of the turning handle requires additional space in the bus as the entire device needs to be pushed out further to ensure clearance is met. The overall size of the unit can create installation challenges especially in situations where there are ducts under the flip seats. Finally, the tensioner does not provide a way to limit the amount of tension the user can exert on the restraint.